Night terrors, also known as sleep terrors, are episodes of intense fear that occur during deep non-REM sleep, usually within the first few hours after falling asleep. They are more common in children but can affect adults as well. During an episode, a person may sit up, scream, thrash, or appear panicked, but often doesn’t remember the event the next morning.

Night terrors differ from nightmares — they do not occur during dreaming and are typically not remembered.